Baghdad -LRB- CNN -RRB- -- At least 29 people were killed and more than 120 others wounded in a dozen car bomb explosions in Baghdad and Kirkuk on Wednesday , police said .

In Baghdad , 10 car bombs exploded in the predominately Shiite neighborhoods , killing 24 people and wounding 110 others Wednesday evening .

The 10 car bombs exploded within two hours in the Baghdad communities of Kadhimiyah , Sadr City , Saidiya , Mashtal , Baghdad al-Jadida , Al-Husseiniyah and Zafraniyah .

Two car bombs exploded in the oil-rich and ethnically mixed city of Kirkuk , about 240 kilometers -LRB- 149 miles -RRB- north of Baghdad . The blasts killed five people and wounded 10 others Wednesday morning , police said .

These attacks came amid growing tensions between Sunnis and Shiites , especially after an incident in Hawija in Kirkuk province , where Iraqi security forces raided a site used by Sunni protesters to demonstrate against the Shiite-led government . A clash between security forces and gunmen last month killed at least 50 people and wounded more than 85 others .

Sunnis , who comprise a minority of Iraqis , had clout during the Saddam Hussein era but have been politically marginalized since his overthrow . Shiites , who make up a majority of Iraqis , now dominate the government .

Since December , tens of thousands of demonstrators have taken to the streets of predominately Sunni provinces -- including Anbar , Nineveh , Salaheddin and Diyala -- demanding that the Shiite-led government stop what they call second-class treatment of Iraq 's Sunni community .

Such turnouts include protests at al-Atisam Square in Hawija .

More people died violently in Iraq in April than in any other month since June 2008 , the United Nations said .

A total of 712 people died and 1,633 more sustained injuries `` in acts of terrorism and acts of violence , '' the UN Assistance Mission for Iraq said .

Civilians made up most of the fatalities , 595 in total . They were also the vast majority of injured , numbering 1,438 . Baghdad saw the most deaths with 697 fatalities .

CNN 's Michael Martinez contributed to this report .

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Ten car bombs in Baghdad explode within two hours , killing 24 people

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Two car bombs in Kirkuk in northern Iraq kill five people

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April is deadliest month since June 2008 , United Nations says

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Tensions are roiling between Sunnis and Shiites